Trawl door construction involving universal and interchangeable components



Dec. 28, 1965 F. J. LUKETA TRAWL DOOR CONSTRUCTION INVOLVING UNIVERSAL AND INTERGHANGEABLE COMPONENTS 9 Sheets-$heet 1 Filed June 18, 1963 INVENTOR. FRANK v'. AukEf/I W69 kW A fra /W945 Dec. 28, 1965 J, LUKETA 3,225,483

TRAWL DOOR CONSTRUCTION INVOLVING UNIVERSAL AND INTERCHANGEABLE COMPONENTS Filed June 18, 1963 9 Sheets-Sheet 2 20 1N VENTOR.

Dec. 28, 1965 F. J. LUKETA 3,225,483

TRAWL DOOR CONSTRUCTION INVOLVING UNIVERSAL AND INTERGHANGEABLE COMPONENTS Filed June 18, 1963 9 Sheets-Sheet 3 INVENTOR. FRANK r/T AHA/774 BY a? Dec. 28, 1965 F. J. LUKETA TRAWL DOOR CONSTRUCTION INVOLVING UNIVERSAL AND INTERCHANGEABLE COMPONENTS 9 Sheets-$heet 4 Filed June 18, 1965 INVENTOR. FPAA/K JUL 67A Dec. 28, 1965 F. J. LUKETA TRAWL DOOR CONSTRUCTION INVOLVING UNIVERSAL AND INTERCHANGEABLE COMPONENTS 9 Sheets-Sheet 5 Filed June 18, 1963 INVENTOR. FRA/VK z]: ll/K6774 Dec. 28, 1965 F. J. LUKETA TRAWL DOOR CONSTRUCTION INVOLVING UNIVERSAL AND INTERCHANGEABLE COMPONENTS 9 Sheets-Sheet 6 INVENTOR. FRANK 1f. ZUA EI'A M- zwmg Filed June 18, 1963 A rraem; Y5

Dec. 28, 1965 F. J. LUKETA TRAWL DOOR CONSTRUCTION INVOLVING UNIVERSAL AND INTERCHANGEABLE COMPONENTS 9 Sheets-Sheet '7 Filed June 18, 1963 INVENTOR. Fem/K u. zz/krA 4 Twelve/5 Dec. 28, 1965 F. J. LUKETA 3,225,483

TRAWL DOOR CONSTRUCTION INVOLVING UNIVERSAL AND INTERCHANGEABLE COMPONENTS Filed June 18, 1963 9 Sheets-Sheet 8 INVENTOR. FRANK J. 10,44. #1

Dec. 28, 1965 F. J. LUKETA 3,225,483

TRAWL DOOR CONSTRUCTION INVOLVING UNIVERSAL AND INTERCHANGEABLE COMPONENTS Flled June 18, 1963 9 Sheets-Sheet 9 INVENTOR. Ae/m K J. BY 7),?

4 rroe/ve z? United States Patent TRAWL DOOR CONSTRUCTION INVOLVING UNI- VERSAL AND INTERCHANGEABLE COMPO- NENTS Frank J. Luketa, 5567 Greenwood Ave. N., Seattle 3, Wash. Filed June 18, 1963, Ser. No. 288,758 6 Claims. (Cl. 439) This application is a continuation-in-part of my copending application Serial No. 269,454, entitled Invertible Trawl Door With Resilient Edge and Adjustable Ballasting, and filed April 1, 1963.

This invention relates to trawl doors of varying sizes, but of common basic construction, such doors involving universal or standard components usable with each size of door. Trawl doors are employed in pairs, one on each side of the trawl net, their function being to spread widely the opposite curtains or wings that precede the net body and lead fish to the entrance of the net body. Each door is in effect an underwater sail. It is towed in the Water in a generally upright position but with its leading face at an angle to the direction of pull. The water contacted by the leading face of the door is deflected thereby, creating a change of momentum and a reaction force acting on the door and having a lateral component moving such door laterally outwardly. The magnitude of the reaction force (and of course its lateral component) and in turn the extent of lateral movement of the door and spread of the curtain or wing of the trawl net vary in accordance with the area of the door. The spread requirements of a trawl net, which requirements in the most part dictate the door size, vary in accordance with the size and type of net, the size and speed capabilities of the trawler, and other factors. It is old to construct trawl doors in several sizes so as to meet the varying spread requirements of different trawl net installations, and heretofore it has been customary to proportionally vary the size of the door components in accordance with the overall size of the door, necessitating the keeping on hand of a separate inventory of replacement door components for each size door. It is a principal object and feature of the present invention to provide a trawl door construction which for the most part consists of standard or universal components, capable of being used with all sizes of the doors constructed in accordance with the invention, whereby the overall inventory of door components may be materially reduced.

In general, the trawl door disclosed and claimed in my aforesaid copending application Serial No. 269,454 comprises a metal door panel, which in lateral crosssection is of a dihedral or shallow V configuration with symmetrical panel portions above and below an apex line or crown, with the forward portion or nose of the panel of a rounded configuration and the trailing edge thereof squared off, but with slightly rounded corners, a rounded, marginal edge or head of cushioning, abrasion resistant, lightweight material, such as cured rubber extending around the nose and side of the panel; buoyancy means in the form of an imperforate buoyant canister; ballasting means in the form of a position adjustable weight contained within a perforated canister; and a bridle connecting to the door at a plurality of spaced apart points and serving to connect the door with a towing warp. It is an object of the present invention to provide a trawl door construction which essentially involves the same components as the said door disclosed in my aforesaid copending application Serial No. 269,454, but wherein at least some of the door components are of sectional construction, detachably connectable to a door panel, and are constructed in a manner giving them universal usage with all sizes of the door panel.

In accordance with one form of the present invention, the transverse configurational characteristics of the door panel, including the overall width of the panel, do not vary from one size door to the next, but only the length of the panel, the location of the anchor points for the bridle legs, and the construction of the panel at such anchor points vary in accordance with panel size. Each door panel of this form of the invention, regardless of its size is symmetrically constructed about a longitudinally extending center line, making the finished door invertible so that it can function as either a port side or a starboard side door.

Modified forms of trawl doors constructed in accordance with the present invention include a door characterized by a door panel that is taller than it is wide (when in its in-use position) wherein either the height dimension or the width dimension of such panel varies from one size door to the next, with the remaining dimension of the two remaining constant.

A further object of the present invention is to provide a set of standard or universal components for a trawl door that are usable on either a port side or a starboard side door.

Another object of the present invention is to provide a trawl door, capable of use in either mid-water or bottom trawling, that is characterized by a relatively lightweight door panel elongated either fore and aft (a particularly advantageous arrangement when the door is used for bottom trawling) or from top to bottom (an advantageous arrangement when the door is used in midwater trawling) and having sectional, marginal edging consisting essentially of a relatively large bead of a wear-resistant, relatively lightweight, resilient cushioning material which is water-lubricated, such as the various kinds of rubber having these features. The'bead of rubber or the like material is bonded to a metal strip which is in turn secured to the door panelby nut and bolt assemblies or the like. The peripheral edge of the door panel involves both straight and curved portions and the jointsbetween the sections of marginal edging are appropriately located so that the sections involving curved portions, hereinafter frequently referred to as standard sections, can be used with each size of door panel constructed in accordance with the present invention. The standard sections of marginal edging are so designed that in the case of the smallest size door panel the standard sections alone provide full marginal coverage of the said panel. In doors involving door panels larger in size than the smallest panel, making up sections of marginal edging are used in conjunction with said standard sections to complete the marginal coverage of the panel.

Another object, feature and advantage of the present invention is to provide a trawl door construction including sectional marginal edging, wherein the constructional characteristics of the edging are such that when the sections of marginal edging extending along the lower edge of the door becomes sufficiently worn that they should be replaced, such worn sections can be easily interchanged with the sections of marginal edging extending along the upper edge of the other door, situated on the opposite side of the trawl net (or even the edging extending along the upper edge of the same door, in the case of some forms of the invention), which are preferably of identical construction.

A further object of the present invention is to provide a trawl door comprising a door panel and sectional edging extending about the margin thereof, with the sectional edging including a bead of rubber or like material and a metal fastening strip, and with either the marginal portion of the door panel or the metal fastening strip including an offset portion to which the other is detachably connected in overlapping relation, such arrangement providing the finished door with a double thickness of metal and an offset at the margin of the door panel, giving the door what might be termed good rim strength. 1

Still another object and feature of the present invention is to provide buoyancy and ballasting means involving end caps having hemispherical portions and other specially formed parts, which end caps are usable with all sizes of doors (i.e. they are universal components) constructed in accordance with the present invention. The buoyancy and ballasting means also involve cylindrical barrel portions which interconnect between pairs of said end caps, with such barrel portions varying in length from one size door to the other (i.e. the barrels are non-universal components).

As yet another object and feature of the invention, certain forms of trawl doors constructed in accordance with the present invention also include detachably mounted transverse stiffening elements and rear edge sweep line rings (door elements to which the sweep lines conmeet) as standard or universal components.

These and other objects, features, advantages and characteristics of the present invention will be apparent from the following description of certain typical and therefore non-limitive embodiments thereof, wherein like letters and numerals refer to like parts, and wherein:

FIG. 1 is an isometric view of a port door constructed in accordance with the present invention, as viewed from the leading or anterior side thereof;

FIG. 2 is an isometric exploded view of the door of FIG. 1, clearly illustrating the sectional nature of the marginal edging, the symmetry of the door panel about its apex line or crown, and the symmetry of the various door elements attachable to the door panel about the apex line of the panel;

FIG. 3 is a side elevational view of a small panel door, taken from the leading or anterior side thereof, illustrating the marginal edging as consisting only of the standard edging sections;

FIG. 4 is a side elevational view of a medium panel door, taken from the same aspect as the view of FIG. 3, and showing relatively small makeup sections of edging employed with the standard sections of edging to complete the marginal covering of the door;

FIG. 5 is a side elevational view of a large panel door, taken from the same aspect as the; views of FIGS. 3 and 4 and showing relatively large makeup edging sections employed with the standard edging sections to provide full marginal coverage of the door;

FIG. 6 is a top plan view of the door of FIG. 3 showing the buoyant canister with a relatively small tubular section, and showing the struts or legs of the bridle substantially connected to the face of the door panel;

FIG. 7 is a top plan view of the door of FIG. 4 showing a buoyant canister having a medium sized tubular section, and showing the struts or legs of the bridle connected to relatively small bosses extending outwardly from the face of the door;

FIG. 8 is a top plan view of the door of FIG. 5 showing a buoyant canister having a relatively large tubular section and showing the bridle connected to relatively large bosses protruding outwardly from the face of the door;

FIG. 9 is a fragmentary, isometric view with certain parts broken away, illustrating the preferred form of canister type ballast means, such form having rounded end caps, a cylindrical barrel and an adjustable ballast weight;

FIG. 10 is a view in side elevation, with parts in section, showing a portion of the ballast canister shown in FIG. 9, the sectioned portions thereof being taken substantially along line 1010 of FIG. 11;

FIG. 11 is a view in lateral cross-section of the canister shown at FIG. 10, being in part taken substantially along line 11-11 thereof;

FIG. 12 is an exploded, fragmentary isometric view on a further enlarged scale, showing additional detail with respect to the end cap of the ballast canister shown at FIGS. 9-11;

FIG. 13 is an isometric fragmentary view illustrating one form of marginal edging and edging mounting means, with detail showing as to the edging-to-panel interconnection;

FIG. 14 is a view in lateral cross-section take substantially along line 1414 of FIG. 13;

FIG. 15 is an isometric fragmentary view, with portions thereof exploded for clarity of illustration, of a modified form of marginal edging and edging mounting arrangement;

FIG. 16 is a view in lateral cross-section, taken substantially along line 1616 of FIG. 15;

FIG. 17 is a small scale side elevational view of a modified form of trawl door, constructed in accordance with the present invention, such view being taken from the leading or anterior side of the door;

FIG. 18 is a top plan View of the door of FIG. 17;

FIGS. 19 and 20 are anterior and posterior side views, respectively, of still a further modified form of the present invention;

FIG. 21 is an isometric exploded view of the trawl door of FIGS. 19 and 20;

FIGS. 22, 23 and 24 present top plan views of three different sizes of the door form illustrated in FIGS. 19-21, FIG. 22 representing a relatively small size door requiring no makeup sections of marginal edging, FIG. 23 representing an intermediate size door involving relatively short makeup sections of marginal edging, and FIG. 24 represents a relatively large size door involving relatively large makeup sections of marginal edging, said FIGS. 22-24 also illustrating a bridle construction wherein all of the parts thereof have universal application with the exception of the front leg and the mounting pads for the rear legs, which vary insize slightly in accordance with the size of the door;

FIG. 25 is a sectional view of the door of FIG. 19, taken substantially along line 2525 of FIG. 19;

FIG. 26 is a top plan view of still another modified form of trawl door constructed in accordance with the present invention wherein the mounting pads for both the front and rear legs of the bridle constitute the variable or non-universal components of the bridle used with this form of door, such bridle including two front as well as two rear legs; and

FIG. 27 is a sectional view of the door shown in FIG. 26, taken substantially along line 2727 of such figure.

Considering FIGS. 1 and 2 in more detail, in such views a port door constructed in accordance with the present invention is selected by way of example to show the construction arrangement and detail of both the port and starboard doors. It will be observed in FIGS. 1 and 2 that the door D1. comprises a metal panel 10, which in lateral cross-section is of a dihedral or shallow V configuration with symmetrical panel portions above and below the apex line or crown 12. The upper and lower portion of the panel 10 are swept back substantially on its leading face, and such panel portions have an angle therebetween of about on the trailing face of the door. Panel 10 is preferably of aluminum construction and may be either cast (e.g. in the case of relatively small doors) or fabricated with sheet stock (e.g. in the case of relatively large doors). The forward portion or nose of the door is prefarably of a rounded configuration and the trailing edge thereof is preferably squared off, with slightly rounded corners.

A rounded, marginal edge or head of cushioning, abrasion resistant, lightweight material such as cured rubber extends around the periphery of the panel. In accordance with the present invention, this marginal edge is sectional, with the sections terminating at appropriate locations so that all sections involving curved parts have universal application with several different sized door panels.

As heretofore mentioned, the marginal edging sections having universal application are termed standard marginal edging sections, and may include upper and lower fore and aft side sections 14, 16, 18, 20, respectively, a nose section 22 and a rear section 24, as illustrated in the drawing, for example. The standard sections of marginal edging are preferably sized to compeltely envelope the periphery of the smallest sized door panel constructed in accordance with the present invention (FIGS. 3 and 6). Thus when such standard sections of marginal edging are employed with relatively larger door panels, as will hereinafter be explained in detail, makeup sections 26, 28 of appropriate length are employed therewith to complete the marginal coverage of the door panel.

The rear edge areas 30, 32 of the panel 10, situated between the respective rear ends of edging side sections 18, 20 and the ends of edging rear section 24, are of a cylindrical configuration and cross-sectionally identical to the bead portions of edging sections 18, 20, 24. However, for purposes of mechanically strong interconnection of the door panel to the sweep lines SL, these edge portions 30, 32 are constructed of metal (being preferably integrally formed with the panel 10) and provide what may be termed saddles. In this form of the invention the saddles 30, 32 serve as anchor points for the coupling means 34 at the ends of the sweep lines SL. The portions of the panel 10 immediately inboard of the edge areas or saddles 30, 32 are cut out and preferably provided with enlarged edge beads 36, 38 to minimize wear on the coupling means 34.

The bridle assembly to which a towing warp T is anchored is mounted onto the leading face of the door and may comprise a single forward leg or strut 40 and upper and lower rear legs 42, 44, respectively. Preferred forms of the bridle are illustrated in the drawings and hereinafter described; however it is to be understood that any suitable type of bridle can be employed, such as the bridle arrangement disclosed in applicants US. Patent No. 3,048,936, issued August 14, 1962, for example, and such as the form of bridle arrangement disclosed in applicants prior US. Patent No. 2,816,385, issued December 17, 1957, simply by way of further example.

The specific form of bridle assembly illutrated in FIGS. 1-8 of the drawings is preferably fabricated or cast of aluminum and the forward leg 40 thereof is attached as by a bolt 46 to the panel 10 at a point laterally centrally placed on the panel and well forward of the center thereof, longitudinally considered. A stiffening boss (not shown) on the trailing side of the panel 10 receives the bolt 46. The rear legs 42, 44 of the bridle assembly are attached by bolts 48, 50 to the face of the panel 18.

In the manner characteristic of the bridle arrangements disclosed and claimed in applicants aforesaid U.S. Patent No. 3,048,936, the bridle assembly is hooked up to the towing warp T at a point downwardly offset from the vertical center of the panel 10 in order that door in use is tilted slightly backwardly so that the water downward thrust against the upwardly facing panel portion is greater 6 than the upward thrust against the downwardly facing panel portion with a desirable resultant water reacting depressing force acting upon the door. For this purpose, when the door is being used as a port door, as illustrated, the hookup to the towing warp T is to an anchor eye 52 laterally offset below the horizontal center line (designated C/L) of the door. A reversely offset anchor eye 54 is also provided for use as the hookup point for the towing warp T when the bridle assembly is inverted for use on a starboard door, as more fully discussed below.

For reasons set forth in my aforementioned copending application Serial No. 269,454, a pair of canisters connect to the trailing side of the door panel 10 inboard of respective upper and lower edges thereof, the upper canister C serving as a buoyancy means, and the lower canister B serving as ballasting means. The mounting arrangement is identical in the case of both types of canisters to enable their interchangeability, depending on which side (either port or starboard) of the net on which the door is to be employed.

FIGS. 9-12 serve to illustrate the preferred form of ballast means, which means comprises the canister B and a ballast weight means W located therein. Canister B comprises a cylindrical barrel 56 interconnected between a pair of elongated hemispherical end caps 58, 60, respectively. The ballast canister B is suitably connected fore and aft to stiffening ribs 62, 64, such as by a bolting arrangement involving external lugs 66, 68 on the canister B through which respective bolts 70, 72 pass. Suitable holes to receive said bolts are provided in the stiffening rib 62, 64, and said stiffening ribs are preferably recessed to cradle the canister B when in attached position, the cradling contour thereof being clearly illustrated in FIG. 11. As best shown in FIG. 9, the ballast weight means W is of cylindrical shape and is suitably of a diameter to more or less snugly fit within the ballast canister B. The ballast canister B comprises a series of flooding holes 76, selected sets of which can accommodate weight positioning bolts 78. Preferably, the bolts 78 are tightened sufficiently to pinch the wall of barrel 56 against the weight W so that the latter is firmly retained without relative movement in the canister B.

The construction permitting the ready connection of end caps 58, 60 onto barrel 56 can be of any suitable arrangement, such as by means of a circumferentially extending flange 80 at the inboard ends of end caps 58, 60 over which the respective ends of the cylindrical barrel slide. The end caps 58, 60 may be non-detachably connected to barrel 56, as by welding, for example, as illustrated in FIG. 10 at 82. Alternatively, caps 58, 60 may be removably secured to barrel 56 as by a plurality of circumferentially arranged nut and bolt assemblies, the bolts extending through openings provided at the ends of barrel 56 and through the caps 58, 6th at the flanges 80.

As best seen in FIG. 2, the buoyancy means or canister C comprises a cylindrical barrel interconnected between end caps 86, 88, and including respective fore and aft lugs 90, 92. Canister C is connected to the stiffening ribs 62, 64 in identical fashion as ballast canister B, i.e. bolts extend through lugs 90, 92 and through holes in the ribs 62, 64, and said canister C is cradled within recess portions of the stiffening ribs 62, 64. In contrast the arrangement of ballast canister B wherein openings 76 are intentionally provided in barrel 56 to let in the water, it is important that buoyancy canister C be watertight, requiring that the respective point of interconnection of barrel 84 to end caps 86, 88 be sealed in suitable fashion and that no openings exist in barrel 84 or in end caps 86, 88.

Referring now to FIGS. 13 and 14, such figures serve to illustrate a typical construction of the marginal edging and its manner of interconnection with the edge of the door panel. In this arrangement the door panel 10 includes an offset flange 94 and the marginal edging includes a metal edging strip 96 and a rubber (or like material) edging strip 98 connected thereto. A series of matched openings are provided at appropriate locations along door flange 94 and metal edging strip 98 for the reception of suitable fastening means such as bolts 100, for example. As most clearly shown in FIG. 14, the metal strip 96 lies against the inside face of the offset flange 94 and is related substantially coplanarly with the main portion of the door panel 10. Preferably, a boss 102 is integrally formed on the outside face of flange 94 around each of the bolt receiving openings formed therein, and such bosses 102 have openings in them of a shape conforming to the heads 104 of bolts 100, so as to serve as a wrench to hold the bolt heads 104 and prevent their turning when the nut 106 is installed. A washer 108 is placed between nut 106 and strip 96. In the region of the abutting together of two sections of marginal edging, such as where makeup section 28 abuts the forward side sections 16 as shown in FIG. 13, for example, a single embossment extends between the adjacent end openings and besides containing the wrench sockets, the elongated, bar-shaped boss 110 serves to add extra section to the door at the joints, such arrangement preventing failure or tearing of flange 94 at the joints.

A particularly advantageous manner of interconnecting the rubber material 98 with the metal strip 96 is illustrated in FIGS. 13 and 14 and involves fabrication of the strip 96 with a series of holes, certain of which are indicated at 112 in such figures, for example, with the rubber material 98 being pressure molded and cured in situ around the metal strip 96 so as to intrabond through the holes 112 and thereby be structurally integrated with the metal strip 96 by mechanical interconnection. The peripheral edge of the strip 96 is preferably cross-sectionally enlarged to improve the panel-to-edging interconnection and to present a blunt edge at 114 to prevent interior cutting of the rubber as the marginal edging flexes in use.

A modified form of marginal edging and associated mounting arrangement is illustrated by FIGS. 15 and 16. In this arrangement the offset and the bosses, designated 102', are located on the metal strip 96, and the peripheral edge of panel is flat. A reinforcing bar 116 spans the joints between adjacent sections of edging and performs the same function that the elongated boss 110 performs in the arrangement of FIGS. 13 and 14. The marginal edging arrangement of FIGS. and 16 has an especially advantageous employment with the form of trawl door (designated D3) that is illustrated by FIGS. 1926, and hereinafter to be described, but is not limited thereto.

As previously mentioned, an extremely important and principal characteristic feature, object and advantage of the bottom trawl door of the present invention is its employment of universal and interchangeable parts. The standard edging sections 14, 16, 18, 20, 22, 24, the bridle, and the end cap 58, 60 and 86, 88 of ballast canister B and buoyancy canister C, respectively, have universal application on several sizes of door panels, as illustrated in FIGS. 38, three sizes of door panels being illustrated by way of example. Also, the just enumerated universal parts are usable on both port and starboard doors, due to the unique construction of the door of the present invention.

The non-universal parts of the door consist of the metal door panel, the makeup sections of edging which must be used with the standard section in the case of the larger doors, and the respective barrel portions of the two canisters.

As clearly illustrated in FIGS. 35, the door panels 10, 10, 10" vary in length but not in height and the crosssectional nose and trailing edge configurations are the same in all cases. As shown in FIG. 3, relating to the small sized door employing the standard sections of edging only, the respective joints between the associated standard side sections 14, 18 and 16, are conveniently located at a point where the edge of the door is straight for a considerable distance on each side of the joint. Thus the makeup sections, such as sections 26, 28 in FIG. 4 and sections 26', 28' in FIG. 5, are straight sections.

Barrels 56, 56, 56" and 84, 84, 84", which constitute the portion of the canisters which vary in length according to the size of the door are also straight sections, involving no special flanges, lugs, etc., such elements being formed on the respective end caps.

Referring again to the door panels and FIGS. 68 in particular, as the length of the door panel changes, the location of point P, representing the point of connection of the bridle to the towing warp T (FIG. 1, for example), changes, such point P moving outwardly away from the panel as the length of the panel increases. All but the smallest sized door panel are provided with bosses or bridle leg extensions (elements 118, 120, 122 in FIGS. 4 and 7 and elements 118', 120', 122 in FIGS. 5 and 8, for example) of sufficient depth to place point P at the desired location while using the same bridle 40, 42, 44.

As another feature of the present invention, a plurality of openings H are provided in the door panel to intercornmunicate the leading and trailing sides of the door. A low pressure is created in the wake of the door, and such openings H serve to reduce the pressure differential existing between the two sides of the door and thus at least to some extent curtail undesirable drag. The openings H represent very smal portions of the area of panel 10 and thus they have only a negligible effect on the spreading function of the door.

FIGS. 17 and 18 present a modified form of door D2 which may advantageously be employed in mid-water trawling operations. Door D2 is characterized by a height dimension that is substantially larger than its width dimension. In this form of the invention, the sectional marginal edging extending around the periphery of door panel 124 includes standard corner sections 126, 128, 130, 132 having end portions curved to conform to the rounded corners of the door panel 124. The marginal coverage of the door panel 124 is completed by a plurality of straight sections 134, 136, 138, 140, 142, 144, some of which may be of standard sizes and be usable with all sizes of the door panel, while the others of such straight sections vary in length in accordance with the panel size and thus constitute makeup sections. As an alternative arrangement, the top to bottom dimension of door D2 may be held constant with the width dimension thereof varying from one size door to the next, in which case standard sections of edging may extend down both sides of the door panel, and the makeup sections, when needed, may be positioned between the respective inboard ends of the top and bottom edge sections of marginal edging.

The door form shown in FIGS. 19-25 is basically similar to the door form illustrated in FIGS. l-8. However, this door, designated D3, comprises a door panel constructed from a piece of P ate aluminum or the like cut and configured into the shape illustrated (noting FIG. 21 in particular). The transverse stiffeners (hereinafter specifically described), the means interconnecting the several legs of the bridle with door panel 145, the means interconnecting the sweep lines with said panel 145, and the mounting means for the buoyancy and ballast canisters are all constructed to be detachably connected to door panel 145. Of these components, all but the means (hereinafter specifically described) for interconnecting the rear leg of the bridle to the door panel 145 and the forward leg of the bridle have universal applicability, i.e., they are usable with all sizes of this form of trawl door.

The edging sections 146, 148, 150, 152, 154, 156, 158 are basically similar to the corresponding sections of marginal edging constituting components of the previously described door form illustrated in FIGS. l-8 except that such edging sections 146, 148, 150, 152, 154, 156, 158

9 involve the previously described mounting arrangement illustrated in FIGS. and 16.

As most clearly shown .in FIG. 20, what maybe termed inside stiffeners 160, 162 extend generally laterally on the posterior side of door panel 145 and are detachably connected at their end to said door panel 145, by nut and bolt assemblies or the like. The inside stiffeners 160, 162 are clearly shown in FIG. 21 as each com-prising a channeliike body portion 164 of generally U-shaped cross-section and flattened end portions 166, 168.

Ball-asting and buoyancy canisters 170, 172, respectively, are basically identical in construction with ballasting and buoyancy canisters B, C, respectively, of the arrangement shown in FIGS. 18, the difference involving the mounting means employed. In the arrangements of FIGS. 21-25, the end caps 174 are all constructed alike and include a circumferentially extending ring or annulus 176 to which a pair of mounting pads 178 connect. Each of said mounting pads 178 include elongated flat portions which are apertured to receive the nut and bolt assemblies or the like used to fasten the canisters 170, 172 to the door panel 145. The end portions 166, 168 of the inside stiffeners 160, 162 are suitably slotted to receive and accommodate a flange portion 180 of one of the mounting pads 178 (FIGS. and 21), and said end portions 166, 168 are provided with spaced apart apertures alignable with the apertures in the flat bases of the mounting pads 178 so that the same nut and bolt assemblies can be used to secure both an end of a stiffener 160, 162 and an end of a canister 170, 172.

A different form of stiffener, designated 182, extends along the rear edge of panel 145 and is detachab-ly connected thereto by means of nut and bolt assemblies or the like extending through openings in a flanged portion 184 of said rear edge stiffener 182 and through openings provided in the rear edge portion of the panel 145. The rear edge stiffener 182 also constitutes a section of the edging and includes a somewhat semi-cylindrical portion 182 that, when section 182 is assembled onto panel 145, constitutes a continuance of the anterior surfaces of edging sections 150, 152. A stiffening element 188 increasing in depth from its end towards its middle preferably forms an integral part of the assembly including flange 184 and curved surface 186 and extends outwardly from said curved surface 186 on the posterior side of the door D3 when said door D3 is assembled.

An element for connecting a sweep line SL with the door panel 10', which may be termed a sweep line ring (designated 190), extends between an end of section 182 and the adjacent end of either section 150 or section 152 of the marginal edging. Each ring 190 includes a tubular portion 192 of the same diameter of and alignable with the bead portion of one or the other of edging sections 150, 152. An enlarged ring 194 surrounds the tubular portion 192, and it is to these rings 194 that the ends of the sweep lines are attached. The inboard end of each element 190 comprises spaced apart tines 196, 198 that extend on 0-pposite side of the panel 145. Aligned openings extend through these tines 196, 198 and the panel 145 to receive the nut and bolt assemblies or the like used to fasten elements 190 to the door panel 145.

The bridle form shown in FIGS. 19-25 comprises a double leg member 200 of generally U-shaue and preferably braced between the leg portions 202, 204 thereof as by a strut 206. Leg portions 292, 204 constitute the rear legs of the bridle and have eye rings 207, 2118, respectively, formed on their terminal ends. At the bight (FIG. 25) a pair of apertured ears 210. 212 extend out from bridle element 266 toward the door panel 145 and are spaced apart to receive an apertured end of the single forward leg 214. As most clearly shown in FIG. 25, forward leg 214 extends in the horizontal plane of the longitudinal center line of door D3. Tow line connection openings 216, 218 are respectively situated above and below such center line, with the tow line being identical to that de- 10 scribed in connection With the door pictured in FIGS. 1-8.

Mounting members 220, 222 characterized by a base portion and two spaced apart apertured ear portions pro jecting outwardly therefrom serve to connect the rearward and forward legs, respectively, of the bridle to the door panel 145. The mounting members 220 are attached to flat surfaces of the door panel and thus their bases are flat while mounting member 220 straddles the longitudinally extending apex line or crown 224 of the door panel 145 and so its base portion is configured to conform with said crown 224 (FIG. 25, for example).

The components of door D3 having universal application, i.e. usable with all sizes of the door panel involved in this form include:

(a) sections 146, 148, 150, 152 and 154 of the resilient marginal edging;

(b) inside stiffeners 160, 162;

(c) rear edge stiffener sections 182;

(d) sweep line connector rings 190;

(e) end caps 174 forming the end pieces of both the ballasting canister and the buoyancy canister 172;

(f) bridle element 200; and

(g) bridle element 222.

The non-universal components or those components that must vary in size as the size of the door panel varies include:

(1) the door panel 145 itself;

(2) the makeup sections 156, 156', 158, 158" of edging;

(3) the cylindrical barrel portions of the cansiters 170,

(4) the forward leg 214 of the bridle; and

(5) the mounting members 220 for the rearward legs of the bridle.

It is to be noted that it is the universal components of the door that involve specially formed portions and in general are relatively more involved or complicated and hence are relatively more costly to manufacture, while the non-universal components are comparatively simple in construction and are less expensive to manufacture. Thus, the present invention not only merely reduces the users inventory of trawl door components, but makes such reduction in the area of the more costly of such components.

FIGS. 22-24 serve to illustrate three sizes of the door form shown in FIGS. 19-21, and such figures show that of the bridle assembly the only components that must vary from one size door to the next are the forward leg (which must be made longer for the larger size doors) and the mounting members for the rear legs of the bridle (the ear portions of which must be made longer for the larger size doors). However, in another form of the door, the mounting members 220, 220', 220" for the rear legs can be the same for all door size-s, with the location of the point of connection of the bridle to the towing warp T being changed from one size door to the 121i? simply by change in the length of the forward leg FIGS. 26 and 27 present a modified form of bridle wherein said bridle comprises two forward legs 226, 228 of identical construction, and a double leg member 230 identical in form to element 200 of the arrangement shown in FIGS. 1925 except for the feature of two pairs of mounting ears 232, 234, respectively, for the two forward legs. In this form of the invention the forward legs 226, 228 are universal components of the door while all four of the mounting members 235 for connecting the four legs with the door panel are nonumversal components, of identical size and construction with each size door. Forward legs 226, 228 include straight body portions and offset eye ring end portions, with the angle of ofliset being the same at each end.

An additional modification involved in the door form of FIGS. 26 and 27 involves the inside stiffeners. In

, through the ears 238 to stiffeners 236 which are under tension.

In summary, it is apparent from the foregoing description that the present invention provides a trawl door that is simple in construction, that is usable as either a port side or a starboard side door, that for the most part is composed of universal parts, usable with several sizes of door panels, and which involves as non-universal parts only straight sections of the least expensive and easiest to manufacture portions of the door. Due to its symmetric construction, the bottom trawl door of the present invention can easily be converted from a port side door to a starboard side door by merely shifting the point of connection of the bridle to the towing warp and also reversing the position of the buoyancy means and the ballasting means. However, if desired, as a substitute for interchanging the buoyancy and ballasting means, changing the towing warp hookup to the bridle, and inverting the entire door, when the marginal edging along the lower side of each door has worn enough to warrant its replacement, the lower side sections of edging need merely be interchanged with the upper side sections or still more simply be replaced with new edging. Also, the sectional construction of the marginal edging permits replacement of a single section of edging when local damage occurs to such section alone, thereby eliminating the need for replacing the whole of the marginal edging all around the periphery of the door, as would be the case if the edging were constructed of a single continuous strip.

From the foregoing, various further modifications, arrangements and adaptations of the present invention will occur to those skilled in the art to which the invention is addressed, within the scope of the following claims.

What is claimed is:

1. A trawl door comprising a relatively thin, metal water reaction panel having a marginal portion; means on said panel for securement of towing warp means leading from a trawler and line means running to a net; a marginal edging consisting of individually removable sections detachably secured to said marginal portion, each said edging section comprising a bead of rubberlike material of sufiicient resiliency and thickness to absorb shock of impact of the edging with solid objects, and a metal fastening strip having an outboard portion secured to said bead of rubber-like material and an inboard portion that overlaps the marginal portion of said panel, thereby providing a double thickness of metal at the margin of the panel and giving the panel a relatively high rim strength for resisting panel distortion; and means detachably securing the inboard portion of said fastening strip to the marginal portion of said panel.

2. A trawl door constructed in accordance with claim 1, wherein the said marginal edge portion of the water reaction panel is offset to one side of, .and extends in substantial parallelism with, the portion of the panel situated immediately inboardly of said marginal portion, with the amount of offset being substantially equal to the thickness of the water reaction panel, and with the metal fastening strip being substantially straight, laterally, and being located in substantially the same plane as the water reaction panel in its extent immediately inboardly of the said marginal portion.

3. A trawl door constructed in accordance with claim 1, wherein the said inboard and outboard edge portions of the fastening strip are each offset to one side of, and extend in substantial parallelism with, the other, with the amount of offset being substantially equal to the thickness of the water reaction panel, with the inboard portion of the fastening strip extending alongside of the marginal portion of the water reaction panel, and with the outboard portion of the fastening strip being located in substantially the same plane with the said marginal portion of the water reaction panel.

4. An invertible trawl door for use in bottom fishing comprising a non-buoyant body constructed to remain generally upright in use, a protective edging extending about the edge of said body, and means interengageable between said body and the protective edging to detachably secure the latter in place, with said body being generally symmetrically constructed about a horizontal center line, and with said protective edging comprising detachable sections extending along the upper and lower edges of said body, and being generally symmetrically arranged about said center line, said edging sections each comprising a head of rubber-like material of sufiicient resiliency and thickness to absorb shock of impact of the edging with solid objects.

5. An invertible trawl door comprising a door panel having generally straight upper and lower edges curving inwardly at the ends of the door, a marginal edging extending about said panel and comprising a plurality of sections, each section being characterized by a mounting strip and a bead of a resilient, abrasive resistant, rubber-like material secured to said mounting strip, and of sufficient resiliency and thickness to absorb shock of impact of the edging with solid objects, and means detachably connecting the mounting strips to the panel, with said marginal edging comprising two edging sections extending along the upper edge of the panel, each including an inwardly curved outboard end portion, and a straight inboard end portion having an end surface substantially abutting the end surface of the other; and two edging sections extending along the lower edge of said panel, each also including an inwardly curved outboard end portion and a straight inboard end portion having an end surface substantially abutting the end surface of the other.

6 An invertible trawl door comprising a water reaction panel having generally straight upper and lower edges curving inwardly at the ends of the door, a marginal edging extending about said panel and comprising a plurality of sect-ions, each section being characterized by a mounting strip and a head of a resilient, abrasive res stant, rubber-like material secured to said mounting strip, and of sufiicient resiliency and thickness to absorb shock of impact of the edging with solid objects, and means detachably connecting the mounting strips to the panel, with said marginal edging comprising two corner sections extending along the upper edge of the door, each of wihch has an inwardly curved outboard end portion and a straight inboard end portion, two corner sections extending along the lower edge of said door, each of which has an inwardly curved outboard end portion and a straight inboard end portion, and at least one makeup sect ons of edging extending between each pair of corner sections, to complete marginal coverage of the upper and lower edges of the panel.

References Cited by the Examiner UNITED STATES PATENTS 1,548,409 8/1925 DeBoer et al. 439 2,066,519 1/1937 Clark 439 2,363,668 11/1944 Groen 43-43.13 XR 2,487,229 11/1949 Finn 43--43.13 2,942,371 6/1960 Johnson et al. 439

FOREIGN PATENTS 452,075 2/ 1913 France. 618,845 12/1926 France.

26,332 1896 Great Britain. 29,539 1897 Great Britain.

(Other References on following page) FOREIGN PATENTS Great Britain. Great Britain. Great Britain. Great Britain. Great Britain.

Switzerland.

14 OTHER REFERENCES Funk and WagnallsNew Standard Dictionary: published 1959 by Funk & Wagnalls Co., New York, pages 155 and 2093.

ABRAHAM G. STONE, Primary Examiner.

P. RAY CHAPPELL, Examiner. 

1. A TRAWL DOOR COMPRISING A RELATIVELY THIN, METAL WATER REACTION PANEL HAVING A MARGINAL PORTION; MEANS ON SAID PANEL FOR SECUREMENT OF TOWING WARP MEANS LEADING FROM A TRAWLER AND LINE MEANS RUNNING TO A NET; A MARGINAL EDGING CONSISTING OF INDIVIDUALLY REMOVABLE SECTIONS DETACHABLY SECURED TO SAID MARGINAL PORTION, EACH SAID EDGING SECTION COMPRISING A BEAD OF RUBBERLIKE MATERIAL OF SUFFICIENT RESILIENCY AND THICKNESS TO ABSORB SHOCK OF IMPACT OF THE EDGING WITH SOLID OBJECTS, AND A METAL FASTENING STRIP HAVING AN OUTBOARD PORTION SECURED TO SAID BEAD OF RUBBER-LIKE MATERIAL AND AN INBOARD PORTION THAT OVERLAPS THE MARGINAL PORTION OF SAID PANEL, THEREBY PROVIDING A DOUBLE THICKNESS OF METAL AT THE MARGIN OF THE PANEL AND GIVING THE PANEL A RELATIVELY HIGH RIM STRENGTH FOR RESISTING PANEL DISTORTION; AND MEANS DETACHABLY SECURING THE INBOARD PORTION OF SAID FASTENING STRIP TO THE MARGINAL PORTION OF SAID PANEL. 